In grapevine protection, it is important to achieve uniform and adequate canopy coverage with spray liquid in vines trained to the double Guyot system. An experiment was conducted in three vineyard rows to compare four standard hollow-cone ATR nozzles (orange, yellow, grey, and red) with different flow rates and two air-induction nozzles, TVI 80-02 and TVI 80-025, designed to reduce spray drift. The nozzles were tested using water and an IDEAL Evolution-P 400 PB axial-fan sprayer. Spray application quality was assessed using water-sensitive papers placed on both sides of the canopy at three heights, approximately 20, 75, and 130 cm from its lower edge. The percentage of coverage and the number of droplet deposits per cm² were determined. The results showed an uneven distribution of spray liquid throughout the canopy. In most treatments, coverage was lower in the upper than in the lower part of the canopy. ATR nozzles produced the highest mean number of droplet deposits at five of the six sampling positions (51 deposits/cm²), whereas TVI nozzles produced the lowest mean number at five of the six positions (9.7 deposits/cm²). With ATR nozzles, the flow rate ranged from 0.80 to 1.63 L/min; however, a higher flow rate did not result in greater canopy coverage. TVI nozzles achieved coverage comparable to ATR nozzles despite fewer droplet deposits per cm². Coverage also differed among canopy heights. With the grey ATR nozzle, mean rear-side coverage increased from 18.1% in the upper part to 73.2% in the lower part, indicating uneven vertical spray distribution. The results suggest combining ATR and TVI nozzles according to canopy position rather than using a single nozzle type over the entire canopy height.
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